Perl MedicTransforming Legacy Code
This title is ordered on demand which may result in extended delivery times.
This book is about taking over Perl code, whether written by someone else or by yourself at an earlier time. Developers regularly estimate that they spend 60 to 80 percent of their time working with existing code. Many problems of code inheritance are common to all languages, but the nature of the language makes Perl especially tricky. The reason why is that Perl is similar to English - bursting with irregular verbs, consistent only when it's convenient, borrowing terms from other languages, and providing many ways to say the same thing. In fact, Perl developers have a motto with the abbreviation TMTOWTDI: There's More Than One Way To Do It. While this flexibility is one of the language's strengths, it also makes it extremely difficult when you are faced with an existing piece of code. There are millions of lines of Perl code being used all over the Web; much of it was built on an ad hoc basis, the creators never imagining that the code would still be in use months or years later. This book will be the resource all Perl programmers need to understand someone else's code, even when it's bad; repair it; convert it to a better style; upgrade it to the latest version of Perl; maintain it; and find and fix its bugs.
- Cure whatever ails your Perl code!
- Maintain, optimize, and scale any Perl software... whether you wrote it or not
- Perl software engineering best practices for enterprise environments
- Includes case studies and code in a fun-to-read format
If you code in Perl, you need to read this book.—Adam Turoff, Technical Editor, The Perl Review.
Scott's explanations of complex material are smooth and deceptively simple. He knows his subject matter and his craft-he makes it look easy. Scott remains relentless practical-even the 'Analysis' chapter is filled with code and tests to run.—Dan Livingston, author of several computer books including Advanced Flash 5: Actionscript in Action
Bring new power, performance, and scalability to your existing Perl code!
Today's Perl developers spend 60-80% of their time working with existing Perl code. Now, there's a start-to-finish guide to understanding that code, maintaining it, updating it, and refactoring it for maximum performance and reliability. Peter J. Scott, lead author of Perl Debugged, has written the first systematic guide to Perl software engineering. Through extensive examples, he shows how to bring powerful discipline, consistency, and structure to any Perl program-new or old. You'll discover how to:
- Scale existing Perl code to serve larger network, Web, enterprise, or e-commerce applications
- Rewrite, restructure, and upgrade any Perl program for improved performance
- Bring standards and best practices to your entire library of Perl software
- Organize Perl code into modules and components that are easier to reuse
- Upgrade code written for earlier versions of Perl
- Write and execute better tests for your software...or anyone else's
- Use Perl in team-based, methodology-driven environments
- Document your Perl code more effectively and efficiently
If you've ever inherited Perl code that's hard to maintain, if you write Perl code others will read, if you want to write code that'll be easier for you to maintain, the book that comes to your rescue is Perl Medic.On the Web Site
Download all of the book's sample code from <www.perlmedic.com>.
Perl or perl? Obtaining Perl. Historical Perl. Who This Book Is For. Typographical Conventions. For Further Reference. Perl Versions. Perl 6. Acknowledgments.
1. Introduction (First Response).
First Things First. Reasons for Inheritance. What Next? Observe the Program in Its Natural Habitat. Get Personal. Strictness. Warnings.
2. Surveying the Scene.
Versions. Part or Whole? Find the Dependencies.
3. Test Now, Test Forever (Diagnosis).
Testing Your Patience. Extreme Testing. An Example Using Test: Modules. Testing Legacy Code. A Final Encouragement.
4. Rewriting (Transplants).
Strategizing. Why Are You Doing This? Style. Comments. Restyling. Variable Renaming. Editing. Line Editing. Antipatterns. Evolution.
5. The Disciplined Perl Program.
Package Variables vs Lexical Variables. Warnings and Strictness. use strict in Detail. use warnings in Detail. Selective Disabling. Caveat Programmer. Perl Poetry.
6. Restructuring (The Operating Table).
Keep It Brief. Cargo Cult Perl. Escaping the Global Variable Trap. Debugging Strategies.
7. Upgrading (Plastic Surgery).
Strategies. Perl 4. Perl 5.000. Perl 5.001. Perl 5.002. Perl 5.003. Perl 5.004. Perl 5.005. Perl 5.6.0. Perl 5.6.1. Perl 5.8.0. Perl 5.8.1. Perl 5.8.2. Perl 5.8.3.
8. Using Modules (Genetic Enhancement).
The Case for CPAN. Using CPAN. Improving Code with Modules. Custom Perls.
9. Analysis (Forensic Pathology).
Static Analysis. Eliminating Superfluous Code. Finding Inefficient Code. Debugging.
10. Increasing Maintainability (Prophylaxis).
Making It Robust. Advanced Brevity. Documentation. Custom Warnings. Version Control System Integration.
11. A Case Study.
The Setup. Triage. Desperately Seeking Sanity. Coming into the 21st Century. Incorporating Modules Effectively, Part 1. Incorporating Modules Effectively, Part 2. Making It Mature, Part 1. Making It Mature, Part 2. Making It Mature, Part 3. Advanced Modification.
12. Conclusion (Prognosis).
In Conclusion. Perl People. A Final Thought.
Appendix: Source Code.
Tie::Array::Bounded. Benchmark::TimeTick. smallprofpp.
About the Author.
The first book to explain how to understand, maintain, update, and improve existing Perl code
° Perl is especially susceptible to maintenance problems, because of its flexible style and ad hoc origins
° Author uses a medical theme throughout, playing off the similarities of doctoring or healing broken code
° Contains the most comprehensive treatment of testing Perl programs ever published, as well as the most comprehensive discussion of Perl version differences
PETER J. SCOTT runs Pacific Systems Design Technologies, providing Perl training, application development, and enterprise systems analysis. He was a speaker on the 2002 Perl Whirl cruise and at YAPC::Canada, and he founded his local Perl Monger group. A software developer since 1981 and a Perl developer since 1992, he has also created programs for NASA's Jet Propulsion Laboratory. Scott graduated from Cambridge University, England, with a Master's of Arts Degree in Computer Science and now lives in the Pacific Northwest with his wife Grace, a cat, and a parrot, at least one of which also uses Perl. He is the lead author of Perl Debugged.